[Ocfs2-devel] [PATCH] ocfs2: drop the unwanted null byte in dentry lock name

[Mark Fasheh]

On Sat, Nov 30, 2013 at 09:45:04AM +0800, Joseph Qi wrote:
> On 2013/11/29 0:40, Mark Fasheh wrote:
> > On Wed, Nov 27, 2013 at 03:38:41PM -0800, Andrew Morton wrote:
> >> On Wed, 27 Nov 2013 17:05:00 +0800 Joseph Qi <joseph.qi at huawei.com> wrote:
> >>
> >>> Dentry lock name is made up of the type 'N', the parent blkno and its
> >>> blkno represented as a binary value.
> >>> Now there is a null byte between parent blkno and the binary blkno
> >>> value, so drop it.
> >>
> >> Geeze.
> >>
> >> What are the runtime effects of this change?
> > 
> > This will change the over-the-wire protocol, so big NACK for this
> > patch please. Some of the lock names are binary and have been forever now.
> > We have a limited amount of space in the name and some lock types would have
> > names too long if we stringified every field.
> > 	--Mark
> > 
> What do you mean by change the over-the-wire protocol?
> In my opinion, the only thing we should do is to make buildup and parse
> consistent.
> But if the new version is mixed mounted with the old, it may have
> problem because of the changed protocol.

That's exactly what "change the over-the-wire protocol" means - "new" and
old versions of the file will not be able to communicate. This is
unacceptable and will anger our users.

We don't make changes like that just to clean up fields.
	--Mark

--
Mark Fasheh